Some games are very good for kids, and adults to play. The relatively mindless first person shooters still stimulate the brain more than watching TV does. The strategy games involve an enormous amount of thought to win at the higher settings, and that's a good thing.
It's easy to criticize games, but, in reality, I don't know that it is always the substitute for more active endeavors. It probably replaces a lot of TV watching, which is very mind numbing and does not stimulate the brain in a meaningful way.
Active thought is very good. Passive interpretation not nearly as much. Porn? I certainly have nothing against it, but I don't know how you can say definitively violent games are better or worse than it. How do you measure this? And how can you say universally one is worse than the other, when the effects on individuals will vary.
One thing is clear. If people can distinguish that porn is just entertainment and not meant as a suggestion for what they should do, the same could be same of games. People can distinguish between reality and fantasy. Most, anyway.